When you run smbd -V on your Snow Leopard installation, you'll see it's running SAMBA version 3.0.28a-apple. While I'm not sure how much difference the "-apple" makes, version 3.0.28a is old. Very old. In other words, it's riddled with bugs. Apple hasn't updated SAMBA in 3 years, and for Lion, they're dumping it altogether for something homegrown. The reason? SAMBA is now GPLv3.

I use it daily at home. My photo-collection is sitting on Synology server, and I access it from all my home computers, including MacOS and Ubuntu. The slowest machine is Windows Xp, but access is fastest, i guess, because of intensive caching. So i use NFS on unix machines, it is also slow, but seems a bit faster.
I do not want to comment employer thing, it is a fud.

I use it daily at home. My photo-collection is sitting on Synology server, and I access it from all my home computers, including MacOS and Ubuntu. The slowest machine is Windows Xp, but access is fastest, i guess, because of intensive caching. So i use NFS on unix machines, it is also slow, but seems a bit faster.
I do not want to comment employer thing, it is a fud.

Synology is just a Linux box so chances are it's running SAMBA. Thus your anecdotal evidence is complete bullshit because if SAMBA was the bottleneck, it would run at the same reduced performance regardless of whether the guest platform was XP, OS X or Linux.

In fact, unless you're specifically mounting Synology's remote share on your Linux guest, the chances are you're not even using SAMBA's FUSE modules to browse SMB shares on that box but instead whatever CIFS API's your desktop environment ships with (FYI Nautilus and KDE both have their own SMB bindings)

This is the great thing about anecdotal evidence - it's usually wrong.

SAMBA has a long and very well documented history of stomping Microsoft at file sharing performance via SMB. Last I really looked (admittedly, some time ago), it was frequently by as much as 30% or better performance.